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91.
Saburo Tamura Shimpei Kuyama Yoshinori Kodaira Shizuo Higashikawa 《Bioscience, biotechnology, and biochemistry》2013,77(2):137-138
The viability of freeze-dried Lactobacillus bulgaricus B-1 was affected by rehydration temperature, and maximum recovery of the viable cells was obtained when they were rehydrated at 20 to 25°C. Cellular ribonucleotides leaked out from the freeze-dried cells during rehydration, but there was no correlation between the viability of cells and the amount of leaked substances. Rehydration of the freeze-dried cells in the presence of RNase caused marked loss of viability. These results suggest that the cell surface was damaged by freeze-drying and its selective permeability was lost to some extent. 相似文献
92.
Akira Isogai Akinori Suzuki Shizuo Higashkawa Shimpei Kuyama Saburo Tamura 《Bioscience, biotechnology, and biochemistry》2013,77(12):3033-3035
( + )-α-Kainic acid (1) was synthesized by starting from a building block, N-Boc-3-acetoxyallylglycine ethyl ester (2). The key intermediate, a methyl 4-[(tert-butoxycarbonyl)prenylamino]-5-hydroxy-2-pentenoate derivative (9), was prepared from 2 in eight synthetic steps. After converting 10 into a methyl ester (11), intramolecular ene-carbocyclization of 11 gave a pyrrolidine derivative (12), which was converted to 1 in a moderate yield. 相似文献
93.
Herbicidal activity of some 50 pyridazyl ethers was evaluated. Among them, 3-chloro-6-(2-phenylphenoxy)-, 3-chloro-6-(2,6-dichlorophenoxy)-, 3-chloro-6-(3-methoxyphenoxy)- and 3-chloro-6-(4-methoxyphenoxy)-pyridazines showed conspicuous effectiveness on radish and millet in pre-emergence test, whereas postemergent activity of the compounds tested was not so remarkable in general. Relationships between herbicidal activity and chemical structure are discussed. 相似文献
94.
Kiyoshi Isono Junsaku Nagatsu Kimie Kobinata Kazuya Sasaki Saburo Suzuki 《Bioscience, biotechnology, and biochemistry》2013,77(2):190-199
Seven additional components, polyoxins C, D, E, F, G, H and I were isolated from polyoxin complex. They have molecular formulae corresponding to C11H15N3O8, C17H23N5O14, C17H23N5O13, C23H30N6O15, C17H25N5O12, C23H32N6O13 and C19H24N4O12, respectively. These polyoxins except inactive polyoxins C and I were highly active against various kinds of phytopathogenic fungi. The close structural similarity among them including polyoxins A and B is also discussed. 相似文献
95.
Series of 3-chloro-6-phenoxy- and 3,6-bisphenoxypyridazines were prepared from 3,6-dichloropyridazine to be evaluated as herbicides. Certain thioethers were also prepared. 相似文献
96.
Saburo Tamura Ching-Fun Chang Akinori Suzuki Sumio Kumai 《Bioscience, biotechnology, and biochemistry》2013,77(3):391-397
Two new isoflavonoids were isolated from red clover as germination inhibitors for the same plant and their structures were determined as a glucoside of biochanin A (7-d-β-glucosyl-5,7-dihydroxy-4′-methoxyisoflavone) (II) and its 5-malonate (I), respectively. Besides these compounds the following substances were also isolated as inhibitors: trifolirhizin (III), ononin (IV), daidzein (V) and its 7-glucoside (VI), formononetin (VII), genistein (VIII) and biochanin A (IX). 相似文献
97.
Yoshio Nakao Tsuneo Kanamaru Masakazu Kikuchi Saburo Yamatodani 《Bioscience, biotechnology, and biochemistry》2013,77(10):2399-2404
The addition of penicillin to cells of Corynebacterium alkanolyticum No. 314 growing on n-paraffins medium caused the simultaneous excretion of phospholipids, UDP-N-acetylhexosamine derivatives and L-glutamic acid.Among many antibiotics which inhibit cell wall synthesis, only the inhibitors of peptideglycan transpeptidase such as penicillin G and cephaloridine were effective for inducing the excretion of phospholipids, UDP-N-acetylhexosamine derivatives and L-glutamic acid, while the others promoted only the excretion of UDP-N-acetylhexosamine derivatives.From the close relationship between the excretion of L-glutamic acid and the excretion of phospholipids, it was suggested that the action of penicillins and cephalosporins on the cell membrane resulted in the excretion of L-glutamic acid. 相似文献
98.
Toshiya Kamikado Ching-Fun Chang Shigeo Murakoshi Akira Sakurai Saburo Tamura 《Bioscience, biotechnology, and biochemistry》2013,77(4):833-836
Two lignans were isolated from leaves of Magnolia kobus DC. as growth inhibitors on silkworm larvae and structurally elucidated as sesamin (I) and kobusin (II) which has been hitherto unknown. 相似文献
99.
100.
Akash Chandela Taeko Watanabe Kenji Yamagishi Yoshihito Ueno 《Bioorganic & medicinal chemistry》2019,27(7):1341-1349
With the aim to create a small interfering RNA (siRNA) with enhanced activity and resistance to nuclease degradation, we synthesized and evaluated the properties of the following siRNAs containing haloalkyl β-d-ribofuranosides at their 3′-dangling ends: 2,2,2-trifluoroethyl β-d-ribofuranoside, 2,2,2-trichloroethyl β-d-ribofuranoside and 2,2,2-tribromoethyl β-d-ribofuranoside. The gene silencing activities of the modified siRNAs were investigated through a dual luciferase reporter assay using HeLa cells. The highest silencing activity was observed for the trichloroethyl analog modified siRNA, which was closely followed by the trifluoroethyl and tribromoethyl analogs. The modified siRNAs were found to show increased binding affinity towards the Piwi-Argonaute-Zwille (PAZ) domain protein based on computational analysis and an experimental study. Furthermore, the RNAs modified with the analogs at their 3′-ends exhibited improved resistance to hydrolysis by a 3′-exonuclease. 相似文献